. in the weeks after 9/11presidentobamaaskedme for what could happen next and we predicted that there would be a lot of attacks like this. it's been a decade and it hasn't happened. now, the fbi has stopped a lot of things before it happened, and initiating people in the united states, but i would have expected a lot more to have happened just like this, and i don't know why it hasn't. >> thanks very much. let's go back to brian in watertown who has been told about a possible controlled explosion that may be imminent. >> they're in the course of doing that. it is 2:00 in the afternoon in the east coast and only several hours of daylight left and the more they can do in daylight the happy they are with about it. they're go about to do that to make sure there are no booby traps in there and agens and police officers will go in following these controlled detonations which will essentially put an end to the risk that something would blow sky high, it will blow as best as they cacon ntrol it. >> that's the home in cambridge, massachusetts. we just leard w moments ago that the police arr at dzokh